A report into the Uvalde school shooting in Texas that killed 21 people has found "systemic failures and egregiously poor decision making" by those involved in the response.
The preliminary report by a committee of the state's House of Representatives was published on Sunday after first being delivered to victims' families.
It details an "overall lackadaisical approach" by authorities at the scene.
Police waited for over an hour outside classrooms before a team entered.
The 18-year-old shooter targeted Robb Elementary School in the Texas town of Uvalde on 24 May.
Nineteen children and two teachers were killed.
The committee believes the nearly-80 page report to be the most complete telling so far of what happened during and after the attack.
It concludes that the school did not adequately prepare for the risk of an armed intruder, and had a culture of leaving doors unlocked or propped open - which goes against security policies in the school district.
Because of failures in maintenance and advanced preparation, the attacker probably killed most of his victims before any responders set foot in the building, the report says.
"Of the approximately 142 rounds the attacker fired inside the building, it is almost certain that he rapidly fired over 100 of those rounds before any officer entered."
There were 376 responders from various agencies at the school on the day of the massacre - most of them from federal and state law enforcement agencies.
The Uvalde schools police chief Pete Arredondo wrote the active shooter response plan, assigning himself as incident commander, but did not consider himself to have assumed that role on the day, he testified.
Mr Arredondo was placed on administrative leave last month and has since resigned.
"The void of leadership could have contributed to the loss of life as injured victims waited over an hour for help, and the attacker continued to sporadically fire his weapon," the report says.
No responder seized the initiative, it adds.
While the report heavily criticises law enforcement, it also says there is no one "to whom we can attribute malice or ill motives," other than the attacker.
Earlier this week leaked CCTV footage from Uvalde was published by a local newspaper, showing the gunman's arrival and police waiting 77 minutes to confront him.
But it was published days before officials said they had planned to show the families or release it publicly.
Latest Stories
-
Fix depreciating Cedi urgently instead of securing new loans – Ato Forson to government
6 mins -
EC should take immediate steps to expand voter registration access – New Force
13 mins -
Women’s Premier League and FA Cup finals set for June 8 at University of Ghana Stadium
21 mins -
Parliament approves $150m loan to tackle Accra floods under GARID project
42 mins -
Banks deny engaging in practices contributing to cedi’s depreciation
54 mins -
Allow legal processes to take place in Kissi Agyebeng’s impeachment case – Vitus Azeem
1 hour -
Livestream: Newsfile discusses cedi depreciation and petition to remove Special Prosecutor
1 hour -
John Kumah to be buried today
1 hour -
It is impossible for EC to rig elections in Ghana – Deputy EC chair
2 hours -
Senegal’s Faye to help resolve Mali, Burkina Faso, and Niger’s impasse
2 hours -
Throwing cash in the air – Nigeria’s wedding dilemma
2 hours -
Bagbin donates public address system to Ghana Law School
2 hours -
TGMA should create a category for Acapella music – Alabaster Box group
2 hours -
Man nabbed for allegedly posing as Asantehene’s staff to fraud victims
2 hours -
Zoomlion sends 18 youths on landmark sanitation mission to Belarus and Russia
2 hours